1. General and Particular Scope of the Invention
The present invention relates in general to cellular telephones and methods of alerting a user to an incoming telephone call, and, in particular, for use with circuitry for monitoring a battery pack for alerting the user to an incoming call on the cellular telephone without using the alarm system of the cellular telephone.
2. Known Prior Art
Cellular telephones are becoming an essential business tool and are appearing everywhere being carried by rushed executives who need to be constantly in touch with their offices. In fact, the annoying sound of a cellular telephone ringing in normally quiet restaurants, concert halls and theaters has led some establishments to ban cellular telephones from their premises under threat of ejection of the user.
As a result of the general disapproval and embarrassment of hearing a cellular telephone ringing in such quiet areas or at inappropriate times, cellular telephone manufacturers have begun adding to their units non-audible alarms in the form of vibrators and lights to provide their users with a choice between an audio or a silent alarm, such as a quiet vibrating alarm or flashing light, to signal incoming telephone calls. Another known solution has been to offer an antenna with a light indicator, such as a LED, that indicates incoming telephone calls.
However, at present there is no known device capable of retrofitting existing cellular telephone units with a non-audible alarm that does not require modification of the internal operating telephone circuitry itself.